My idea is, again, a polishing phase thing, but I see some more potential in the current main menu, which might not be noticed yet. Instead of that "list" type of selecteable options (come on, we see those boring stuffs in a lot of game's main menu), how about being a bit more unique, and making the actual objects on the screen interactive? Something similar to this:
Without the list, there is more free space on screen, so the garage could be also brought to vision, with the current chosen car spinning, on it's maintenance platform, with some crew members welding it, or just minding their business, or even the pilot itself fidgeting around with a tablet-like thing.
If you hover the cursor over the objects, they start to highlight, or animate (wheels start to spin slowly for e.g.). If you click the specified object, the game could utilize more the already awesome 3D menu, and the camera could make a circle around the CLICKED object, then settle down in front of the car in another angle, thus bringing forth the sub-menu.
Would be a banger of a feature, and yes, i know this is a resource sink too, but, well, first impressions are significant aswell.